Substituted-(aminosulfonylamino) pyridine thiocarboxylic acids and derivatives thereof

ABSTRACT

Disclosed are pyridinecarboxylic acids and derivatives thereof which are useful as intermediates for the preparation of 1H-pyrido(2,3-c or 4,3-c) (1,2,6)thiadiazin-4(3H)-one-2,2-dioxide compounds and derivatives thereof which are useful as herbicides.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a division of application Ser. No. 676,591, filedApr. 13, 1976, now U.S. Pat. No. 4,014,888 which in turn is acontinuation-in-part of Application Ser. No. 572,024, filed Apr. 28,1975, now abandoned which in turn is a division of Application Ser. No.412,944, filed Nov. 5, 1973, now U.S. Pat. No. 3,920,641 issued Nov. 18,1975.

SUMMARY OF THE INVENTION

The present invention is directed to novel 1H-pyrido(2,3-c or4,3-c)(1,2,6-thiadiazin-4(3H)-one-2,2-dioxide compounds represented bythe formulae: ##STR1## wherein: EACH X independently representsloweralkyl, haloloweralkyl, cycloalkyl, --SO₂ R⁵, --SO₂ aryl, Y'R⁵,CCl₃, CF₃, SCN, ##STR2## aryl, aryloxy, --NR³ R⁴, halo, nitro, --SO₂ NR³R⁴, --COOR⁵ or Y"CF₂ CZ₃ ;

n represents an integer of 0 to 3, inclusive;

m represents an integer of 1 or 2;

Each Y, Y' and Y" independently represent oxygen or sulfur;

R¹ and R² each independently represent hydrogen, loweralkyl,haloloweralkyl, alkenyl, haloalkenyl, alkynyl, haloalkynyl, cycloalkyl,aryl, benzyl, benzoyl, benzenesulfonyl loweralkoxyalkyl, Y'R⁵, --SCCl₃,##STR3## NH₂, --SO₂ R⁵, ##STR4## dialkylaminoalkyl, pyrrolidinoethyl,piperidinoethyl, morpholinoethyl, ##STR5## or --C(CH₃)₂ C.tbd.N; each R³and R⁴ independently represents hydrogen or loweralkyl;

Each R⁵ represents loweralkyl;

Each Z independently represents hydrogen, bromo, chloro or fluoro; and

Where at least one of R¹ and R² is hydrogen, the salts thereof withorganic or inorganic bases.

The above-described compounds of this invention have been found to beactive herbicides against a wide range of plant species. Accordingly, amethod of the present invention of controlling undersirable vegetationcomprises applying a herbicidally effective amount of one or more of theabove-described compounds to the plant, the area or plant locus wherecontrol is desired.

For the sake of brevity and simplicity, the term "active ingredient(s)"is used hereinafter in this specification to broadly describe the novel1H-pyrido-1,2,6-thiadiazin-4(3H)-one-2,2-dioxide compounds.

DETAILED DESCRIPTION

A herbicide is used herein to mean a compound which controls or modifiesthe growth of plants. By a "growth controlling amount" is meant anamount of compound which causes a modifying effect and includesdeviations from natural development, such as, for example, killing,retardation, defoliation, desiccation, regulation, stunting, tillering,stimulation, dwarfing and the like. By "plants" it is meant germinantseeds, emerging seedlings and established vegetation, including theroots and aboveground portions.

The term "alkyl" or "loweralkyl" is used herein and in the appendedclaims to designate a straight or branched chain radical containing,where not otherwise expressly defined, from 1 to about 6 carbon atoms,such as, for example, methyl, ethyl, propyl, isopropyl, 2-methylpropyl,butyl, isobutyl, tert-butyl, pentyl, hexyl and the like.

The terms "halo" and "halogen", where employed herein, represent iodine,chlorine, fluorine and bromine. The term "cycloalkyl" is employed tomean radicals such as, for example, cyclopropyl, cyclobutyl,cyclopentyl, cyclohexyl and other cycloalkyl groups. The term "aryl"designates phenyl and substituted phenyl such as tolyl, halophenyl andthe like.

The term "alkenyl" as employed in the present specification and claimsdesignates an alkenyl radical containing from about 3 to about 6 carbonatoms, inclusive, such as, for example, propenyl, 2-methyl propenyl,butenyl, hexenyl and the like which optionally may bear one or morehalogen substituents. The term "alkynyl" as used herein and in theappended claims designates an alkynyl radical of from about 3 to about 6carbon atoms, inclusive, such as, for example, propynyl, 2-methylpropynyl, butynyl, pentynyl, hexynyl and the like which optionally maybear one or more halogen substituents.

Those skilled in the art will appreciate the availability andpossibility of substitution of the pyridyl portion of the moleculecorresponding to Formulas I, II, III and IV with substituents depictedby X_(n) is limited only by the preselected values for X and n andsteric considerations involved in placement of substituents about amolecule within a finite space.

The active ingredients of the present invention are usually crystallinesolids when pure which are soluble in the usual organic solvents andsomewhat insoluble in water. The active ingredients of the presentinvention are suitable for use as herbicides, especially aspost-emergent herbicides. Certain of the active ingredients have beenfound to be particularly useful as selective herbicides in the presenceof desired crops. The1H-pyrido(2,3-c)(1,2,6)thiadiazine-4(3H)-one-2,2-dioxide compounds ofFormula I constitute a preferred embodiment of the present invention.Another preferred class of compounds are the1H-pyrido(4,3-c)(1,2,6)thiadiazin-4(3H)-one-2,2-dioxide compounds ofFormula II. In an additional embodiment, preferred compounds of FormulasI and II are those wherein R¹ is loweralkyl. In a further embodiment ofthe present invention, compounds of Formula I or II wherein n is 1 and Xis loweralkyl of from 1 to about 6 carbon atoms are preferred. In anadditional embodiment, compounds of Formulas I and II wherein X is haloand R¹ is loweralkyl are preferred. In still another embodiment,compounds of Formula I wherein n is 1, X is loweralkyl of from one toabout four carbon atoms, R¹ is loweralkyl and R² is hydrogen arepreferred. In a further embodiment, compounds of Formula I wherein n is1, X is halo, R¹ is loweralkyl and R² is hydrogen are preferred.

The active ingredients of the present invention can be prepared bycyclizing pyridinecarboxylic acid derivatives of the formulae: ##STR6##wherein T is selected from the group consisting of hydroxy, alkoxycontaining from 1 to about 3 carbon atoms and halo, all othersubstituents being as previously defined herein.

A preferred group of compounds are those wherein T is as herein aboveset forth, n is 2 and R² is hydrogen. Under this above group a morepreferred group of compounds are those of the formulae ##STR7## whereineach X independently represents loweralkyl, of 1 to 6 carbon atoms,haloloweralkyl of 1 to 6 carbon atoms, cycloalkyl of 3 to 6 carbonatoms, SR⁵, OR⁵, aryl wherein aryl is phenyl, halophenyl or tolyl, --NR³R⁴, halo or nitro;

n represents an integer of 0 to 3, inclusive;

Y represents oxygen or sulfur;

T represents a member selected from the group consisting of hydroxy,alkoxy of 1 to 3 carbon atoms, and halo;

R' represents hydrogen, loweralkyl of 1 to 6 carbon atoms,haloloweralkyl of 1 to 6 carbon atoms, alkenyl of 3 to 6 carbon atoms,haloalkenyl of 3 to 6 carbon atoms, alkynyl of 3 to 6 carbon atoms,haloalkynyl of 3 to 6 carbon atoms, cycloalkyl of 3 to 6 carbon atoms,aryl wherein aryl is phenyl, halophenyl or tolyl, benzyl,loweralkoxyalkyl wherein each of alkoxy and alkyl are of from 1 to 6carbon atoms, dialkylaminoalkyl wherein each alkyl is of from 1 to 6carbon atoms, pyrrolidinoethyl, piperidinoethyl, morpholinoethyl or--C(CH₃)₂ C.tbd.N;

each of R³ and R⁴ independently represents hydrogen or loweralkyl of 1to 6 carbon atoms;

R⁵ represents loweralkyl of 1 to 6 carbon atoms.

An especially preferred group of compounds are those wherein:

n is 1,

Y is oxygen or sulfur,

X is loweralkyl or halo,

T is alkoxy and

R¹ is loweralkyl.

Another especially preferred group of compounds are those wherein:

n is 2,

Y is oxygen

X is loweralkyl and/or halo,

T is alkoxy and

R¹ is loweralkyl.

The reaction conditions for the ring closure generally depend upon thetype of CYT substituent. In carrying out the preparation of thecompounds of the instant invention the selected pyridinecarboxylic acidderivative is cyclized to the desired corresponding active ingredient ofthe instant invention with a condensing agent. Representative examplesof condensing agents include, for example, phosphorus oxychloride,thionyl chloride or aqueous or alcoholic alkaline solutions such as, forexample, methanol and sodium methylate, aqueous sodium hydroxide or thelike. The reaction is carried out under ambient atmospheric pressuresand the reactants are usually employed in stoichiometric amounts,although an excess amount of the condensing agent may be employed.

The reaction is usually carried out at temperatures of from about 0° C.to about 150° C., and usually from about 25° C. to about 110° C. Whenemploying sodium methylate and methanol as the condensing agent, thereaction is preferably carried out by heating the reaction mixture atthe reflux temperature. The reaction is ordinarily completed in a periodof from about 10 minutes to about 24 hours. Following the substantialcompletion of the reaction, the reaction mixture is cooled, acidified toa pH of from about 1.0 to about 4.5, filtered and evaporated in vacuo toremove the solvent. The residue thus obtained is extracted with suitablesolvent, such as, for example, acetone, benzene, methylene chloride,chloroform, ether, or the like, and the combined extracts filtered andevaporated in vacuo to obtain the desired product as a crystallinesolid. If desired, the product can be further purified byrecrystallization from a suitable solvent or solvent mixture such as,for example, ethanol, carbon tetrachloride, chloroform, cyclohexane orthe like.

Alternatively, the reaction mixture is subjected to evaporation in vacuofollowing the completion of the reaction and the residue thus obtainedmixed with water. The resulting aqueous mixture is then acidified withconcentrated hydrochloric acid to a pH of from about 1.0 to about 4.5 toprecipitate the desired product therefrom.

Where aqueous solutions of the condensing agent are employed, thereaction is usually conducted at room temperature upon completereaction. The reaction mixture can be extracted with a selected solventsuch as, for example, ether, methylene dichloride or the like, prior toacidification of the aqueous layer to remove non-acidic impurities andthe resultant aqueous layer acidified as above to obtain the desiredproduct.

If desired, the recovered product can be further purified byrecrystallization from a suitable solvent such as hereinbeforementioned.

Compounds of Formulas I or II wherein R² is hydrogen can, followingcyclization as previously set forth, be converted to compounds where R¹is other than hydrogen by reacting the same with typical alkylating,aralkylating, etc., agents such as, e.g., methyl iodide, dimethylsulphate, ethyl bromide, n-butyl bromide, crotyl bromide, benzylbromide, and p-bromobenzyl chloride, also the most variously substitutedalkyl halides and halides of carbonic acid, carboxylic acids, sulphonicacids and esters, amides and nitriles of halogen carboxylic acids andother types of selected compounds corresponding to the meaning of R² setforth hereinbefore.

Such reactions can be performed in inert polar organic solvents such asalkanones, the dimethyl ether of ethylene glycol or the like or in thepresence of alkali carbonates or bicarbonates.

The intermediate compounds of Formulas V and VI employed in preparingthe desired 1H-pyrido(2,3-c or4,3-c)(1,2,6)thiadiazin-4(3H)-one-2,2-dioxide compounds are also noveland constitute an additional embodiment of this invention. Suchcompounds can be prepared by reacting a selected substituted aminopyridinecarboxylic acid reactant of the formulae: ##STR8## wherein T isas previously defined and wherein X, Y and n are as previously defined,with a selected sulfamoyl halide reactant of the formula:

    halo · SO.sub.2 NHR.sup.1

the reaction is carried out in the presence of a solvent carrier underambient pressure, usually with stirring. Representative solvent carriersinclude, for example, benzene, toluene, xylene, acetonitrile, chloroformand the like. The reaction is ordinarily carried out at temperatures offrom about 0° C. to about 110° C., preferably from about 25° C. to about85° C., for a period of from about 1 to about 48 hours.

The reactants are usually employed in substantially equimolar amountsand the hydrogen chloride generated during the reaction can be tied upby the use of equimolar amounts of agents such as, for example, calciumcarbonate, triethylamine or the like. Following the completion of thereaction, the reaction mixture is cooled, filtered and the filtrateevaporated in vacuo to remove the solvent carrier. The residue thusobtained is extracted with a selected solvent, such as, for example,ethanol, cyclohexane or the like and the combined extracts cooled toprecipitate the desired product which can be further purified if desiredby recrystallization.

Substituents in the 4, 5, 6 or 2, 5, 6 ring positions of theintermediates of Formula V or Formula VI, respectively, may beintroduced after cyclization of the same to the corresponding1H-pyrido(2,3-c or 4,3-c)-(1,2,6)thiadiazin-4(3H)-one-2,2-dioxidecompound.

The following examples illustrate the present invention and the mannerby which it can be practiced but, as such, should not be construed aslimitations upon the overall scope of the same.

EXAMPLE 13-(1-methylethyl)-1H-pyrido(2,3-c)(1,2,6)-thiadiazin-4(3H)-one-2,2-dioxide

Methyl 2((((1-methylethyl)amino)sulfonyl)-amino)-2-pyridine carboxylate(10.4 grams; 0.038 mole) and sodium methoxide (6.2 grams; 0.115 mole)were mixed with 200 milliliters (mls) of methanol and the resultingreaction mixture heated at reflux temperatures for a period of about 5hours. Following the substantial completion of the reaction, thereaction mixture was cooled and acidified to a pH of about 1.0 withhydrogen chloride. The mixture was filtered and the filtrate evaporatedin vacuo to obtain a gummy residue. The residue was extracted withacetone, the combined extracts filtered and evaporated in vacuo to yieldthe crude product. Further purification of the product was accomplishedby washing with benzene and recrystallization of the same from arefluxing chloroform-cyclohexane solution. As a result of theseoperations, the desired 1H-pyrido(2,3-c or4,3-c)(1,2,6)thiadiazin-4(3H)-one-2,2-dioxide compound was obtained as awhite solid having a melting point of 194.5° C.-196° C.

EXAMPLE 23-Methyl-1H-pyrido(2,3-c)(1,2,6)thiadiazin-4(3H)-one-2,2-dioxide

Methyl 2(((methylamino)sulfonyl)amino)-3-pyridine carboxylate (11.0grams; 0.045 mole) was dissolved in 150 ml of methanol and sodiummethoxide (7.3 grams; 0.135 mole) added thereto. The resulting reactionmixture was heated at reflux temperatures for a period of about fourhours. After cooling the reaction mixture, the solvent was removed invacuo and the residue thus obtained suspended in 30 ml of water and theresulting suspension acidified to a pH of about 1.0 with concentratedhydrochloric acid. The reaction mixture was filtered and the precipitatethus obtained was washed with several portions of water and dried invacuo. As a result of such operations, the desired title compound wasobtained as a white powder having a melting point of 290° C.-292° C.

EXAMPLE 33-n-propyl-1H-pyrido(2,3-c)(1,2,6)thiadiazin-4(3H)-one-2,2-dioxide

Methyl 2-(((n-propylamino)sulfonyl)amino)-3-pyridinecarboxylate (15.7grams; 0.057 mole), 95 ml of water and 10.5 ml of 50 percent aqueoussodium hydroxide were mixed and the resulting reaction mixture stirredfor about 11/4 hours at ambient temperatures. The reaction mixture wasextracted with two -- 50 ml portions of methylene chloride and one -- 50ml portion of ether to remove impurities. The aqueous layer wasseparated from the organic layer and acidified to a pH of about 4.5 withconcentrated hydrochloric acid. The solution was filtered and thefiltrate acidified to a pH of about 1. The resulting product precipitatewas recovered by filtration, dissolved in acetone and the solutionfiltered and dried with magnesium sulfate. The mixture was againfiltered and the filtrate reduced in vacuo to obtain the title compoundas a yellow powder having a melting point of 208° C.-210° C.

EXAMPLE 41-Methyl-3-(1-methylethyl)-pyrido(2,3-c)-(1,2,6)thiadiazin-4(3H)-one-2,2-dioxide

3-(1-Methylethyl)pyrido(2,3-c)(1,2,6)thiadiazin-4(3H)-one-2,2-dioxide(5.0 grams; 0.0208 mole) was mixed with 50 ml of diethylene glycoldimethyl ether. The system was flushed with nitrogen and sodium hydride(1.0 gram; 0.02 mole), previously washed with n-hexane, was addedportionwise to the reaction mixture. After the effervescence of hydrogenceased, 2.2 ml of dimethyl sulfate (0.023 mole, 1.33g/ml) was added andthe reaction mixture heated at reflux temperatures for a period of 4hours. During the reaction, the color of the reaction mixture changedfrom light yellow to deep red and gradually back to yellow.

Following the completion of the reaction, the reaction mixture wascooled and filtered and the solvent removed in vacuo. The solid residuethus obtained was recrystallized at -10° C. from 50 ml of ethanol toobtain the desired title compound as a light yellow solid having amelting point of 138° C.-139° C.

Other active ingredients of the instant invention are similarly preparedby employing procedures analogous to those set forth in Examples 1 thru4 above and the foregoing teachings of the specification by cyclizing aselected substituted amino pyridine carboxylic acid reactant with acondensing agent. Such other products corresponding to Formulas I andII: ##STR9## are set forth in the following Table I.

                                      TABLE I                                     __________________________________________________________________________    Cmpd.                                                                             For-                Ring                                                  No. mula                                                                              X.sub.n         Position                                                                             R.sup.1    R.sup.2   Y m                       __________________________________________________________________________    5   I   --              --     C.sub.2 H.sub.5                                                                          H         O 2                       6   I   Cl              6                                                     i-C.sub.3 H.sub.7                                                                 H   O               2                                                     7   I   CH.sub.3        7                                                     i-C.sub.3 H.sub.7                                                                 H   O               2                                                     8   I   2-methylpropyl  7                                                     i-C.sub.3 H.sub.7                                                                 H   O               2                                                     9   I   --              --     2-methylpropyl                                                                           H         O 2                       10  I   --              --     n-butyl    H         O 2                       11  I   Cl              6      n-butyl    H         O 2                       12  II  CH.sub.3        7                                                     i-C.sub.3 H.sub.7                                                                 H   O               2                                                     13  II  Cl              8                                                     i-C.sub.3 H.sub.7                                                                 H   O               2                                                     14  II  --              --     2-methylpropyl                                                                           H         S 1                       15  I   CH.sub.3        5,6,7  n-C.sub.6 H.sub.13                                                                       CH.sub.3  S 1                       16  II  CH.sub.3        5,7,8  n-C.sub.3 H.sub.12 Cl                                                                    i-C.sub.3 H.sub.7                                                                       O 2                       17  I   5-CH.sub.3, 7-OCH.sub.3                                                                       5,7    phenyl     H         S 1                       18  II  5-Br, 7,8-diC.sub.2 H.sub.5                                                                   5,7,8  n-C.sub.4 H.sub. 9                                                                       C.sub.2 H.sub.5                                                                         O 2                       19  II  5-C.sub.6 H.sub.13, 7-F                                                                       5,7    H          H         S 1                       20  II  Br              5,7,8  NH.sub.2   cyclobutyl                                                                              O 2                       21  II  7-CH.sub.3, 8-NO.sub.2                                                                        7,8    cyclopropyl                                                                              NH.sub.2  S 1                       22  I   Br              5,6,7  cyclopropyl                                                                              CH.sub.3  O 2                       23  I   5-Cl, 7-I       5,7    CH.sub.3   cyclopropyl                                                                             S 1                       24  I   5,6-diCl, 7-CH.sub.3                                                                          5,6,7  H          phenyl    S 2                       25  I   5-Cl, 6-OCH.sub.3, 7-CH.sub.3                                                                 5,6,7  CH.sub.2 Cl                                                                              H         O 1                       26  I   CH.sub.2 Cl     5,6    SO.sub.2 CH.sub.3                                                                        OCH.sub.3 S 2                       27  I   cyclopropyl     6      OCH.sub.3  SCH.sub.3 O 1                       28  I   SO.sub.3 CH.sub.3                                                                             5,7    SCH.sub.3  CH.sub.2 CHCH.sub.2                                                                     O 2                       29  I   OCF.sub.2 CHCl.sub.2                                                                          6      CH.sub.2 CCH                                                                             n-C.sub.4 H.sub.9                                                                       O 2                       30  I   SO.sub.2 phenyl 7      n-C.sub.6 H.sub.13.sup.-                                                                 morpholinoethyl                                                                         S 2                       31  I   OC.sub.3 H.sub.7                                                                              5,6    cyclohexyl NH.sub.2  S 1                       32  I   CCl.sub.3       5      C.sub.2 H.sub.5 NHCH.sub.3                                                               H         O 1                       33  I   5-CCl.sub.3, 7-CH.sub.3                                                                       5,7    CH.sub.2 OCH.sub.3                                                                       phenyl    O 2                       34  I   CF.sub.3        5,7    C(CH.sub.2).sub.2 CN                                                                     cyclohexyl                                                                              O 1                       35  I                                                                                  ##STR10##      6      (CH.sub.2).sub.4 CCH                                                                     SO.sub.2 CH.sub.3                                                                       S 2                       36  I   5-CH.sub.3, 6-phenyl                                                                          5,6    (CH.sub.2).sub.4 CCH.sub.2                                                               H         S 1                       37  I   5-Cl, 7-p-tolyl 5,7    H          (CH.sub.2).sub.4 CCH                                                                    S 2                       38  I   phenyl          6      benzoyl    H         O 2                       39  I   NHCH.sub.3      7      (CH.sub.2).sub.4 CC1CHCl                                                                 OH        O 2                       40  I   SO.sub.2 N(CH.sub.3).sub.2                                                                    6      C.sub.2 H.sub.5                                                                          (CH.sub.2).sub.3 C CCl                                                                  S 2                       41  I   COOC.sub.6 H.sub.13                                                                           5      SO.sub.2 -phenyl                                                                         H         O 1                       42  I   SCF.sub.2 CF.sub.3                                                                            5,7                                                   i-C.sub.3 H.sub.7                                                                  ##STR11##                                                                        S               1                                                     43  I   SC.sub.3 H.sub.13                                                                             6      CH.sub.3                                                                                  ##STR12##                                                                              O 2                       44  I   5-C.sub.2 H.sub.5, 7-SO.sub.2 NHC.sub.6 H.sub.13                                              5,7    pyrrolidinoethyl                                                                         CH.sub.3  O 2                       45  I   5,6-diCl, 7-NO.sub.2                                                                          5,6,7                                                                                 ##STR13## (CH.sub.2).sub.4 CHCH.sub.2                                                             S 2                       46  I   6-COOCH.sub.3, 7-C.sub.6 H.sub.13                                                             6,7    piperidinoethyl                                                                          n-C.sub.6 H.sub.13                                                                      S 1                       47  I   5-SCN, 7-cyclohexyl                                                                           5,7    SO.sub.2 C.sub.6 H.sub.13                                                                phenyl    S 2                       48  I   6-SCH.sub.3, 7-SO.sub.2 C.sub.6 H.sub.13                                                      6,7    (CH.sub.2).sub.6 O(CH.sub.2).sub.4                                            CH.sub.3   H         O 2                       49  I   5-Cl, 6-CH.sub.3, 7-C.sub.6 H.sub.13                                                          5,6,7  1-pentyl   C(CH.sub.3).sub.2 CN                                                                    O 2                       50  II  5-CH.sub.3, 7,8-diC.sub.6 H.sub.13                                                            5,6,7  morpholinoethyl                                                                          i-C.sub.3 H.sub.7                                                                       S 2                       51  II  5-OCH.sub.3, 7,8-diNO.sub.2                                                                   5,7,8  C.sub.3 H.sub.6 Br                                                                       NH.sub.2  O 2                       52  II  SCH.sub. 3      5,7                                                   i-C.sub.3 H.sub.7                                                                 CH.sub.3                                                                          O               1                                                     53  II  5-NO.sub.2, 7-SC.sub.6 H.sub.13                                                               5,7                                                                                   ##STR14## H         S 1                       54  I   5-CF.sub.3, 7-C.sub.6 H.sub.13 Br                                                             5,7    NH.sub.2   SO.sub.2 C.sub.6 H.sub.13                                                               O 2                       55  II  5-OC.sub.5 H.sub.7, 7-CCl.sub.3                                                               5,7    (CH.sub.2).sub.2 CCCl                                                                    2-methylpropyl                                                                          S 2                       56  II  5-CF.sub.3, 7-C.sub.6 H.sub.13 Cl                                                             5,7    C(CH.sub.3).sub.6 CN                                                                     CH.sub.3  O 2                       57  II  7-CH.sub. 3, 8-OCF.sub.2 CCl.sub.3                                                            7,8    i-C.sub.3 H.sub.7                                                                        H         O 2                       58  II  5-phenyl, 8-SCF.sub.2 CH.sub.3                                                                5,8    phenyl     piperidinoethyl                                                                         O 2                       59  II  5-NO.sub.2, 7,8-CCl.sub.3                                                                     5,7,8  CH.sub.2 CHCH.sub.2                                                                      t-butyl   S 2                       60  II  5-cyclopropyl, 7-CH.sub.2 Br                                                                  5,7    H          (CH.sub.2).sub.2 CClCHCl                                                                S 1                       61  II  SO.sub.2 phenyl 7      benzyl     i-C.sub.3 H.sub.7                                                                       O 2                       62  II  5-SO.sub.2 CH.sub.3, 7-CCl.sub.3                                                              5,7    H          cyclopropyl                                                                             O 2                       63  II  5-F, 7-SC.sub.2 H.sub.5                                                                       5,7    CH.sub.3   CH.sub.2 CHCH.sub.2                                                                     S 2                       64  II  5,8-di-OCH.sub.3, 7-OC.sub.2 H.sub.5                                                          5,7,8  C(CH.sub.3).sub.2 CCH                                                                    CH.sub.2 C CH                                                                           S 2                       65  II  7-CF.sub.3, 8-OC.sub.6 H.sub.13                                                               7,8    benzoyl    CH.sub.3  S 1                       66  II  5-cyclohexyl, 7,8-diCH.sub.3                                                                  5,7,8  i-C.sub.3 H.sub.7                                                                        SCCl.sub.3                                                                              O 2                       67  II  5-NO.sub.2, 7-cyclopentyl, 8-Cl                                                               5,7,8  H          (CH.sub.2).sub.4 CHCH.sub.2                                                             S 2                       68  II  5-C.sub.2 H.sub.5, 7-SO.sub.2 C.sub.6 H.sub.13                                                5,7    cyclopropyl                                                                              OC.sub.3 H.sub.7                                                                        O 2                       69  II                                                                                 ##STR15##      5,7    i-C.sub.4 H.sub.9                                                                        SO.sub.2 CH.sub.3                                                                       S 1                       70  II  COOC.sub.6 H.sub.13                                                                           5,7                                                                                   ##STR16## SCH.sub.3 O 1                       71  II  7-NH.sub.2, 5,8-di-CF.sub.3                                                                   5,7,8  cyclohexyl C.sub.2 H.sub.5                                                                         O 2                       72  II  7-NHCH.sub.3, 5,8-diCH.sub.3                                                                  5,7,8  i-C.sub.5 H.sub.11                                                                       SO.sub.2 C.sub.6                                                                        O.sub.13                                                                        2                       73  II  7-N(CH.sub.3).sub.2, 5,8-diCl                                                                 5,7,8  NH.sub.2                                                                                  ##STR17##                                                                              S 1                       74  II  5-NHC.sub.6 H.sub.13, 8-phenyl                                                                5,8    SO.sub.2 -phenyl                                                                         H         O 2                       75  II  phenoxy         5,7    i-C.sub.3 H.sub.7                                                                        morpholinoethyl                                                                         O 2                       76  II  5-SCN, 7,8-diBr 5,7,8  CH.sub.2OC.sub.2 H.sub.5                                                                 H         S 2                       77  II  N(CH.sub.3).sub.2                                                                             5,8    OCH.sub.3  cyclohexyl                                                                              O 2                       78  II  5-SO.sub.2 NH.sub.2, 7-isobutyl                                                               5,7    CH.sub.2 Br                                                                              CH.sub.2 Br                                                                             S 1                       79  II  5,7-diSO.sub.2 NHCH.sub.3                                                                     5,7    p-tolyl    SO.sub.2 C.sub.3 H.sub.7                                                                S 2                       80  II  5-SCN, 7-SO.sub.2 NHC.sub.6 H.sub.13                                                          5,7    OCH.sub.3  OCH.sub.3 O 2                       81  II  5-CH.sub.3, 7-COOC.sub.3 H.sub.7                                                              5,7    phenyl     phenyl    O 1                       82  II                                                                                 ##STR18##      5,7    SCCl.sub.3 n-C.sub.4 H.sub.9                                                                       O 2                       83  II  CF.sub.3        5,8    i-C.sub.3 H.sub.7                                                                        C.sub.6 H.sub.12 Cl                                                                     O 2                       84  II  OCF.sub.2 CHCl.sub.2                                                                          5,8    CH.sub. 2 N(CH.sub.2).sub.2                                                              H         O 1                       85  II  5-SCF.sub.2 CF.sub.3, 8-CH.sub.3                                                              5,8                                                                                   ##STR19## C(CH.sub.3).sub.2 CN                                                                    S 2                       86  II  5,8-diCl, 7-OCF.sub.2 CH.sub.3                                                                5,7,8  pyrrolidinoethyl                                                                         CH.sub.2 CHCH.sub.2                                                                     S 2                       87  II  5-SCH.sub.3, 8-phenoxy                                                                        5,8    2-methylpropyl                                                                            ##STR20##                                                                              S 1                       88  II  5,8-diNO.sub.2, 7-OCF.sub.2 CHBr.sub.2                                                        5,7,8  piperidinoethyl                                                                          CH.sub.3  O 2                       89  II  5-CCl.sub.3, 7-cyclopropyl                                                                    5,7    H          benzoyl   O 2                       90  II  5-NH.sub.2, 7-CCl.sub.3                                                                       5,7                                                                                   ##STR21## H         S 2                       91  II  2-methylpropyl  5,7    CH.sub.2 CHCH.sub.2                                                                      benzyl    S 1                       92  II  cyclopropyl     5,8    morpholinoethyl                                                                          i-C.sub.3 H.sub.7                                                                       O 2                       93  II  5-CH.sub.2 CHCl.sub.2, 7-SCN                                                                  5,7                                                                                   ##STR22## NH.sub.2  O 2                       94  I   6-CH.sub.3, 7-phenyl                                                                          6,7    i-C.sub.3 H.sub.7                                                                        H         O 2                       95  I   C-Cl, 7-CH.sub.3                                                                              6,7    i-C.sub.3 H.sub.7                                                                        H         O 2                       96  I   CH.sub.3        5,7    i-C.sub.3 H.sub.7                                                                        H         O 2                       97  I   C.sub.2 H.sub.5 7      i-C.sub.3 H.sub.7                                                                        H         O 2                       __________________________________________________________________________

The following examples illustrate the preparation of the novelintermediates of Formulas V and VI which are used to prepare theherbicidally active compounds corresponding to Formulas I and II.

EXAMPLE 98 Methyl 2-((((1-methylethyl)amino)sulfonyl)amino)-3-pyridinecarboxylate

Methyl 2-amino-3-pyridine carboxylate (10.0 grams; 0.066 mole) andisopropyl sulfamoyl chloride (11.4 grams; 0.066 mole) were mixed with300 ml of benzene and the resulting reaction mixture heated at refluxtemperatures for a period of 48 hours. Following the reaction period,the reaction mixture was cooled and the solvent removed in vacuo. Theoily residue thus obtained was extracted with 200 ml of cyclohexane andthe extracts combined and cooled. The resulting precipitate wasrecovered by filtration and recrystallized from carbon tetrachloride. Asa result of these operations, the desired title compound having amelting point of 121°-123° C. was obtained.

EXAMPLE 99 Methyl 2-(((methylamino)sulfonyl)amino)-3-pyridinecarboxylate

Methyl 2-amino-3-pyridine carboxylate (15.2 grams; 0.1 mole), calciumcarbonate (13.0 grams; 0.1 mole) and methylsulfamoyl chloride (13.0grams; 0.1 mole) were mixed with 200 ml of acetonitrile and theresulting reaction mixture stirred at ambient temperatures for a periodof about 15 hours. Following the reaction period, the reaction mixturewas filtered and the solvent removed in vacuo. The semi-solid residuethus obtained was extracted with ethanol. A white crystallineprecipitate, obtained by filtering the extract solution, wasrecrystallized from ethanol and the desired title compound having amelting point of 133°-139° C. was obtained.

Other representative intermediates corresponding to Formulas V and VIare similarly prepared by employing procedures analogous to those setforth in the preceding examples and the foregoing teachings of thespecification by reacting selected substituted aminopyridinecarboxylates with a selected substituted sulfamoyl halide reactant. Suchintermediates include the following representative compounds:

Methyl 2-(((propylamino)sulfonyl)amino)-3-pyridine carboxylate;

Methyl 6-methyl-2-((((1-methylethyl)amino)sulfonyl)amino)-3-pyridinecarboxylate;

Methyl 2-(((ethylamino)sulfonyl)amino)-3-pyridine carboxylate;

Methyl 5-chloro-2-((((1-methylethyl)amino)sulfonyl)amino)-3-pyridinecarboxylate;

Methyl6-(2-methylpropyl)-2-((((1-methylethyl)amino)sulfonyl)amino)-3-pyridinecarboxylate;

Methyl 2-((((2-methylpropyl)amino)sulfonyl)amino)-3-pyridinecarboxylate;

Methyl 2-(((n-butylamino)sulfonyl)amino)-3-pyridine carboxylate; and

Methyl 5-chloro-2-(((n-butylamino)sulfonyl)amino)-3-pyridinecarboxylate.

The compounds of the present invention have been found to be suitablefor use in methods for the pre- and post-emergent control of weeds orother unwanted vegetation. Certain of the active ingredients of thepresent invention have been found to be active against undesiredvegetation in the presence of desired crop plants while producing only anegligible effect on the crop plants. For all such uses, unmodifiedactive ingredients of the present invention can be employed. However,the present invention embraces the use of a herbicidally-effectiveamount of the active ingredients in composition form with a materialknown in the art as an adjuvant or carrier in solid or liquid form.Thus, for example, an active ingredient can be dispersed on a finelydivided solid and employed therein as a dust. Also, the activeingredients, as liquid concentrates or solid compositions comprising oneor more of the active ingredients, can be dispersed in water, typicallywith the aid of a wetting agent, and the resulting aqueous dispersionemployed as a spray. In other procedures, the active ingredient can beemployed as a constituent of organic liquid compositions, oil-in-waterand water-in-oil emulsions, or water dispersions, with or without theaddition of wetting, dispersing, or emulsifying agents.

Suitable adjuvants of the foregoing type are well known to those skilledin the art. The methods of applying the solid or liquid herbicidalformulations similarly are well known to the skilled artisan.

As organic solvents used as extending agents there can be employedhydrocarbons, e.g., benzene, toluene, xylene, kerosene, diesel fuel,fuel oil, and petroleum naphtha ketones such as acetone, methyl ethylketone and cyclohexanone, chlorinated hydrocarbons such as carbontetrachloride, chloroform, trichloroethylene, and perchloroethylene,esters such as ethyl acetate, amyl acetate and butyl acetate, ethers,e.g., ethylene glycol monomethyl ether and diethylene glycol monomethylether, alcohols, e.g., methanol, ethanol, isopropanol, amyl alcohol,ethylene glycol, propylene glycol, butyl Carbitol acetate and glycerine.Mixtures of water and organic solvents, either as solutions oremulsions, can be employed.

The active ingredients can also be applied as aerosols, e.g., bydispersing them in air by means of a compressed gas such asdichlorodifluoromethane or trichlorofluoromethane and other Freons andGenetrons, for example.

The active ingredients of the present invention can also be applied withadjuvants or carriers such as talc, pyrophyllite, synthetic fine silica,attapulgus clay, kieselguhr, chalk, diatomaceous earth, lime, calciumcarbonate, bentonite, fuller's earth, cottonseed hulls, wheat flour,soybean flour, pumice, tripoli, wood flour, walnut shell flour, redwoodflour and lignin.

As stated, it is frequently desirable to incorporate a surface activeagent in the compositions of the present invention. Such surface activeor wetting agents are advantageously employed in both the solid andliquid compositions. The surface active agent can be anionic, cationicor nonionic in character.

Typical classes of surface active agents include alkyl sulfonate salts,alkylaryl sulfonate salts, alkylaryl polyether alcohols, fatty acidesters of polyhydric alcohols and the alkylene oxide addition productsof such esters, and addition products of long chain mercaptans andalkylene oxides. Typical examples of such surface active agents includethe sodium alkylbenzene sulfonates having 10 to 18 carbon atoms in thealkyl group, alkylphenol ethylene oxide condensation products, e.g.,p-isooctylphenol condensed with 10 ethylene oxide units, soaps, e.g.,sodium stearate and potassium oleate, sodium salt of propylnaphthalenesulfonic acid, di(2-ethylhexyl)ester of sodium sulfosuccinic acid,sodium lauryl sulfate, sodium decane sulfonate, sodium salt of thesulfonated monoglyceride of coconut fatty acids, sorbitan sesquioleate,lauryl trimethyl ammonium chloride, octadecyl trimethyl ammoniumchloride, polyethylene glycol lauryl ether, polyethylene glycol estersof fatty acids and rosin acids, e.g., Ethofat 7 and 13, sodiumN-methyl-N-oleyl taurate, Turkey Red Oil, sodium dibutyl naphthalenesulfonate, sodium lignin sulfonate, polyethylene glycol stearate, sodiumdodecylbenzene sulfonate, tertiary dodecyl polyethylene glycol thioether(nonionic 218), long chain ethylene oxide-propylene oxide condensationproducts, e.g., Pluronic 61 (molecular weight 1000), polyethylene glycolester of tall oil acids, sodium octyl phenoxyethoxyethyl sulfate,tris(polyoxyethylene)sorbitan monostearate (Tween 60), and sodiumdihexyl sulfosuccinate.

The concentration of the active ingredients in liquid compositionsgenerally is from about 0.001 to about 95 percent by weight or more.Concentrations of from about 0.001 to about 50 weight percent are oftenemployed. In dusts or dry formulations, the concentration of the activeingredient can be from about 0.001 to about 95 weight percent or more;concentrations of from about 0.001 to about 50 weight percent are oftenconveniently employed. In compositions to be employed as concentrates,the active ingredient can be present in a concentration of from about 5to about 98 weight percent. The active ingredient compositions can alsocontain other compatible additaments, for example, phytotoxicants, plantgrowth regulants, pesticides and the like and can be formulated withsolid particulate fertilizer carriers such as ammonium nitrate, urea andthe like.

The present compositions can be applied by the use of power-dusters,boom and hand sprayers, spray-dusters, by addition to irrigation water,and by other conventional means. The compositions can also be appliedfrom airplanes as a dust or a spray because they are effective in verylow dosages.

The exact dosage to be applied is dependent not only upon the specificactive ingredient being employed, but also upon the particular plantspecies to be modified and the stage of growth thereof, as well as thepart of the plant to be contacted with the toxic active ingredient.Thus, it is to be understood that all of the active ingredients of theinvention and compositions containing the same may not be equallyeffective at similar concentrations or against the same plant species.In non-selective pre-emergence and foliage treatments the compositionsof this invention are usually applied at an approximate rate of fromabout 1 to about 25 pounds per acre, but lower or higher rates may beappropriate in some cases. In selective post-emergence operations tofoliage, a dosage of from about 0.06 to about 5.0 pounds per acre isusually employed but higher dosages may be necessary in some instances.In view of the foregoing and following disclosures, one skilled in theart can readily determine the optimum rate to be applied in anyparticular case.

So as to illustrate the general and selective phytotoxic properties ofthe active ingredients of the present invention, a group of controlledgreenhouse experiments is described below.

Various species of plants were planted in beds of good agricultural soilin a greenhouse. After the plants had emerged and grown to a height ofabout 2-6 inches, certain of the plants were sprayed with a given volumeof a 4000 parts per million concentration solution of the candidateactive ingredient, prepared by mixing the selected active ingredient andemulsifier or dispersant with water, corresponding to a rate ofapproximately 12.0 pounds per acre. Other plants were left untreated toserve as controls.

After a period approximately 14 days, the effect of each of the testingredients on the plants was evaluated by a comparison with the controlgroup of plants.

In such operations, each of the3-(1-methylethyl)-1H-pyrido(2,3-c)(1,2,6)thiadiazin-4(3H)-one-2,2-dioxide(Compound A);3-n-propyl-1H-pyrido(2,3-c)(1,2,6)thiadiazin-4(3H)-one-2,2-dioxide(Compound B);3-ethyl-1H-pyrido(2,3-c)(1,2,6)thiadiazin-4(3H)-one-2,2-dioxide(Compound C) and6-chloro-3-(1-methylethyl)-1H-pyrido(2,3-c)(1,2,6)thiadiazin-4(3H)-one-2,2-dioxide(Compound D) test ingredients was found to give complete control of theplant species bindweed and velvet leaf. Additionally, each of the7-methyl-3-(1-methylethyl)-1H-pyrido(2,3-c)(1,2,6)thiadiazin-4(3H)-one-2,2-dioxide(Compound E);3-n-butyl-1H-pyrido(2,3-c)(1,2,6)thiadiazin-4(3H)-one-2,2-dioxide(Compound F); and6-chloro-3-n-butyl-1H-pyrido(2,3-c)-(1,2,6)thiadiazin-4(3H)-one-2,2-dioxide(Compound G) test ingredients was found to give substantially completecontrol of weed species annual morning glory and velvet leaf. In otheroperations, each of the3-methyl-1H-pyrido(2,3-c)(1,2,6)thiadiazin-4(3H)-one-2,2-dioxide(Compound H), Compound A and Compound D test ingredients were found togive substantial control of foxtail. In further operations, the3-(1-methylethyl)-7-(2-methylpropyl)-1H-pyrido(2,3-c)(1,2,6)thiadiazin-4(3H)-one-2,2-dioxide(Compound I) test ingredient was found to give complete control ofvelvet leaf plants while each of3-n-butyl-1H-pyrido(2,3-c)(1,2,6)thiadiazin-4(3H)-one-2,2-dioxide(Compound J),1-methyl-3-(1-methylethyl)-pyrido(2,3-c)(1,2,6)thiadiazin-4(3H)-one-2,2-dioxide(Compound K), Compound B, Compound D, Compound E and Compound G wasfound to give complete control of pigweed plants.

In representative pre-emergence operations, seeds of selected weedspecies are planted in seedbeds and, while exposed, sprayed withcompositions containing an active test ingredient. The seeds are thencovered with a layer of soil and the test beds maintained underconditions conducive to growth for a period of about 14 days. The testcompositions are prepared as set forth hereinbefore. In suchrepresentative operations, Compound A was found to completely inhibitthe growth of velvet leaf seeds at a dosage rate of about 10 pounds peracre and of annular morning glory seeds at a dosage rate of about 2.0pounds per acre.

In additional representative selective post-emergence operations,Compound A was found to give substantially complete control of bindweed,velvet leaf and annual morning glory plants at dosage rates of fromabout one-fourth to about one-half pound per acre with only slight or noeffects on desired crop plant species of rice, wheat, corn and sorghumat such low dosage rates. No damage to such desired plant species wasobserved at dosage rates as high as about 8.0 pounds per acre.

In further representative selective post-emergence operations, CompoundD was found to give substantial control of pigweed, bindweed, velvetleaf and annual morning glory at dosage rates of from about one-fourthto about one-half pound per acre while causing no damage to corn, rice,wheat and sorghum at such dosage rates. Compound C was likewise found togive substantial control of pigweed and bindweed at dosage rates ofabout one-fourth to about 2.0 pounds per acre while causing little or nodamage to desired corn, rice, wheat, sorghum and soybean plants.

In still other post-emergence operations, Compound B was found to givesubstantial control of bindweed and Compound E was found to givesubstantial control of velvet leaf and annual morning glory at dosagerates of as low as about one-fourth pound per acre with substantially nodamage to corn, rice, wheat and sorghum plants.

Preparation of Starting Materials

The amino pyridine carboxylic acid derivatives employed as startingmaterials in the present invention are for the most part known materialsand/or are materials which can be prepared employing known procedures.

The appropriate 2-amino pyridine carboxylic acids can be prepared byconversion of an appropriately substituted 3-cyano-2-pyridinol (preparedby the procedure of either Mariella, J. Am. Chem. Soc. 69, 2670 (1947)or Org. Syn. Coll. Vol IV, 210) to the 2-chloro-3-cyanopyridine (Juliaet al., Bull. Soc. Chem. France (1966) Vol. 7, 2387). Subsequentamination (Taylor et al., J. Org. Chem. 19, 1633 (1954)) and hydrolysis(Brunskill, J. Chem. Soc. (C), 960 (1968)) affords the desired 2-aminopyridine carboxylic acid.

The appropriate 2-amino pyridine carboxylic acid esters can be preparedby the procedure taught by Dornon et al., Ber., 73 542 (1940).

The appropriate 4-amino pyridine carboxylic acids and esters can beprepared by one or more of the procedures taught in Kirpal, Monatash 23,239 (1895); Fox, J. Org. Chem. 17, 547 (1952); Nakashima et al., NipponKagaku Zasshi 81, 816 (1960); Bordendorf et al., Arch. Phar. 290, 494(1957) and Wang et al., Tetrahedron 27, 2581 (1971).

The amino pyridine carboxylic acids or esters wherein X is either haloor nitro can be prepared by subjecting the unsubstituted amino pyridinecarboxylic acid or ester to the appropriate halogenation or nitrationreaction employing standard procedures.

The appropriate amino pyridine acyl halides can be prepared by employingknown procedures of converting carboxylic acids, salts or esters to acylhalide employing inorganic acid halides. Such procedures are taught inWagner et al., Synthetic Organic Chemistry, pages 546-549, (1965) JohnWiley & Sons, Inc., New York.

The sulfamoyl halide reactants employed as starting materials in thepresent invention are all known compounds.

Although the invention is described with respect to specificmodifications, the details thereof are not to be construed aslimitations except to the extent indicated in the following claims.

What is claimed is:
 1. A compound of the formulae: ##STR23## wherein:each X independently represents loweralkyl, of 1 to 6 carbon atoms,haloloweralkyl of 1 to 6 carbon atoms, cycloalkyl of 3 to 6 carbonatoms, SR⁵, OR⁵, aryl wherein aryl is phenyl, halophenyl or tolyl, --NR³R⁴, halo or nitro;n represents an integer of 0 to 3, inclusive; Yrepresents sulfur; T represents a member selected from the groupconsisting of hydroxy or alkoxy of 1 to 3 carbon atoms; R' representshydrogen, loweralkyl of 1 to 6 carbon atoms, haloloweralkyl of 1 to 6carbon atoms, alkenyl of 3 to 6 carbon atoms, haloalkenyl of 3 to 6carbon atoms, alkynyl of 3 to 6 carbon atoms, haloalkynyl of 3 to 6carbon atoms, cycloalkyl of 3 to 6 carbon atoms, loweralkoxyalkylwherein each of alkoxy and alkyl are of from 1 to 6 carbon atoms,dialkylaminoalkyl wherein each alkyl is of from 1 to 6 carbon atoms or--C(CH₃)₂ C.tbd.N; each of R³ and R⁴ independently represent hydrogen orloweralkyl of 1 to 6 carbon atoms; R⁵ represents loweralkyl of 1 to 6carbon atoms.
 2. The compound of claim 1 wherein n is 0, T is alkoxy andR' is alkyl.
 3. The compound of claim 1 wherein n is 1, X is loweralkyl,T is alkoxy and R' is loweralkyl.
 4. The compound of claim 1 wherein nis 1, X is halo, T is alkoxy and R' is loweralkyl.
 5. The compound ofclaim 1 wherein n is 2, X is halo, T is alkoxy and R' is loweralkyl. 6.The compound of claim 1 wherein n is 2, X is halo and loweralkyl, T isalkoxy and R' is loweralkyl.
 7. The compound of claim 1 wherein T ishydroxy.